This book explores the fundamental concepts, basic theory, and key principles of 802.11 networks with roaming capabilities. Today, we increasingly expect to find public Wide Local Area Network (WLAN) 802.11 access in our airports, public spaces, and hotels, and we want to maintain our connections when we're mobile and using 802.11 WLANs. However, 802.11 was not originally designed with roaming capabilities and can't, in its ''pure'' form, support seamless roaming between different hotspots and other 802.11 access points. This book details the theory behind various 802.11 extensions to permit roaming and describes how these extensions can be successfully implemented in 802.11 WLANs. Coverage of User Authentication in 802.11 is reviewed as is roaming between 802.11 and other wireless technologies. Wireless technologies and application programming interfaces are given their due with generous coverage as well. * Offers a comprehensive treatise on Wi-Fi 802.11 roaming by comparing/contrasting it to cellular roaming theory and techniques * Emerges as a ''one stop'' resource for design engineers charged with fulfilling the market need for seamless 802.11 device roaming capabilities * Builds upon the knowledge base of a professional audience without delving into long discussions of theory long since mastered
Author(s): Paul Goransson, Raymond Greenlaw
Series: Communications Engineering
Publisher: Newnes
Year: 2007
Language: English
Pages: 368
Front Cover......Page 1
Secure Roaming In 802.11 Networks......Page 4
Copyright Page......Page 5
Table of Contents......Page 8
Preface......Page 16
Acknowledgments......Page 20
About the Authors......Page 24
1.1 Introduction......Page 26
1.2 Basic Networking Terminology and Conventions......Page 28
1.3 Setting the Scene......Page 30
1.4 Different Notions of Roaming......Page 33
1.5 Big Cells, Little Cells......Page 37
1.6 Authentication, Authorization, Accounting, and Roaming......Page 42
1.7 How Fast Do We Roam on the Range?......Page 44
1.8 Taxonomy for Roaming......Page 46
1.9 Organization of the Book......Page 52
2.1 Introduction......Page 54
2.2 The Future of Computing......Page 55
2.3 Basic Concepts......Page 56
2.4 Early History of Radio Telephony......Page 57
2.5 The Digital Revolution......Page 65
2.6 Soft Versus Hard Handoffs in Various Cellular Technologies......Page 75
2.7 The Quest for Convergence......Page 76
2.8 Summary......Page 85
3.1 Introduction......Page 88
3.2 Primer on the 802.11 Standard......Page 89
3.3 Introduction to 802.11 Roaming......Page 104
3.4 Local Roaming......Page 111
3.5 Global Roaming......Page 113
3.6 Mobile IP and Its Role in 802.11 Roaming......Page 117
3.7 Those Pesky Laws of Physics......Page 122
4.1 Introduction......Page 126
4.2 Evolution of an IEEE Standard......Page 127
4.3 Battle for Speed, Cost, and Market Dominance......Page 131
4.4 The 802.11 Standard’s Physical Layer......Page 133
4.5 Fast Secure Roaming Task Groups......Page 136
4.6 802.11i Security......Page 137
4.7 802.11e Quality of Service......Page 142
4.8 802.11k Radio Resource Measurement Enhancements......Page 145
4.9 802.11r Roaming......Page 149
4.10 Other 802.11 Subgroups......Page 152
4.11 Wi-Fi Alliance Versus IEEE 802.11......Page 153
5.1 Introduction......Page 158
5.2 The Driver and Client in an 802.11 Station......Page 159
5.3 Detailed Analyses of Real-Life Roams......Page 178
5.4 Dissection of a Global Roam......Page 181
5.5 Dissection of a Local Roam......Page 184
5.6 Access-Point Placement Methodologies......Page 189
6.1 Introduction......Page 194
6.2 802.1X Port-Level Authentication......Page 195
6.3 The AAA Server......Page 198
6.4 The Extensible Authentication Protocol......Page 202
6.5 Flexible and Strong Authentication in 802.11......Page 209
6.6 Other 802.11 Authentication Methodologies......Page 212
6.7 Network Access Control......Page 213
6.8 Summary......Page 217
7.1 Introduction......Page 220
7.2 The 802.11 Security Staircase......Page 221
7.3 Preauthentication in 802.11i......Page 223
7.4 Detailed Analysis of Real-Life Secured Roams......Page 225
7.5 Dissection of a WPA-PSK Protected Roam......Page 226
7.6 Dissection of a WPA2 Enterprise Roam......Page 228
7.7 Dissection of an 802.11i Preauthentication......Page 235
7.8 Summary......Page 243
8.1 Introduction......Page 244
8.2 Voice over Wireless IP Roaming......Page 245
8.3 Opportunistic Key Caching......Page 252
8.4 Centralized Wireless Switch Architectures......Page 254
9.1 Introduction......Page 260
9.2 Overview of the 802.11r Standard......Page 261
9.3 Detailed Concepts and Terminology of 802.11r......Page 263
9.4 Protocol Exchanges in 802.11r......Page 275
9.5 The 802.11k Standard Applied to Roaming......Page 282
9.6 Concluding Remarks......Page 289
10.1 Introduction......Page 292
10.2 Ideal Roaming Experience......Page 295
10.3 IEEE 802.16: WiMAX......Page 296
10.4 IEEE 802.15.1: Bluetooth......Page 298
10.5 Relevant Standards Bodies and Industry Organizations......Page 299
10.6 Third Generation Partnership Program......Page 301
10.7 UMA: A Transitional Step for 3GPP......Page 311
10.8 Third Generation Partnership Program 2......Page 312
10.9 The 802.21 Standard......Page 314
10.10 Summary......Page 319
11.1 Introduction......Page 322
11.2 Survey of Ongoing Work Related to 802.11......Page 323
11.3 A Mobility Model for Studying Wireless Communication......Page 332
11.4 Conclusions......Page 337
Appendix A. Acronyms and Abbreviations......Page 340
Appendix B. List of Figures......Page 352
Appendix C. List of Tables......Page 357
Index......Page 358
